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/*
* Copyright (C) 2009 Apple Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
* OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef RepatchBuffer_h
#define RepatchBuffer_h
#if ENABLE(JIT)
#include "CodeBlock.h"
#include <MacroAssembler.h>
#include <wtf/Noncopyable.h>
namespace JSC {
// RepatchBuffer:
//
// This class is used to modify code after code generation has been completed,
// and after the code has potentially already been executed. This mechanism is
// used to apply optimizations to the code.
//
class RepatchBuffer {
typedef MacroAssemblerCodePtr CodePtr;
public:
RepatchBuffer(CodeBlock* codeBlock)
{
JITCode& code = codeBlock->getJITCode();
m_start = code.start();
m_size = code.size();
ExecutableAllocator::makeWritable(m_start, m_size);
}
~RepatchBuffer()
{
ExecutableAllocator::makeExecutable(m_start, m_size);
}
void relink(CodeLocationJump jump, CodeLocationLabel destination)
{
MacroAssembler::repatchJump(jump, destination);
}
void relink(CodeLocationCall call, CodeLocationLabel destination)
{
MacroAssembler::repatchCall(call, destination);
}
void relink(CodeLocationCall call, FunctionPtr destination)
{
MacroAssembler::repatchCall(call, destination);
}
void relink(CodeLocationNearCall nearCall, CodePtr destination)
{
MacroAssembler::repatchNearCall(nearCall, CodeLocationLabel(destination));
}
void relink(CodeLocationNearCall nearCall, CodeLocationLabel destination)
{
MacroAssembler::repatchNearCall(nearCall, destination);
}
void repatch(CodeLocationDataLabel32 dataLabel32, int32_t value)
{
MacroAssembler::repatchInt32(dataLabel32, value);
}
void repatch(CodeLocationDataLabelCompact dataLabelCompact, int32_t value)
{
MacroAssembler::repatchCompact(dataLabelCompact, value);
}
void repatch(CodeLocationDataLabelPtr dataLabelPtr, void* value)
{
MacroAssembler::repatchPointer(dataLabelPtr, value);
}
void relinkCallerToTrampoline(ReturnAddressPtr returnAddress, CodeLocationLabel label)
{
relink(CodeLocationCall(CodePtr(returnAddress)), label);
}
void relinkCallerToTrampoline(ReturnAddressPtr returnAddress, CodePtr newCalleeFunction)
{
relinkCallerToTrampoline(returnAddress, CodeLocationLabel(newCalleeFunction));
}
void relinkCallerToFunction(ReturnAddressPtr returnAddress, FunctionPtr function)
{
relink(CodeLocationCall(CodePtr(returnAddress)), function);
}
void relinkNearCallerToTrampoline(ReturnAddressPtr returnAddress, CodeLocationLabel label)
{
relink(CodeLocationNearCall(CodePtr(returnAddress)), label);
}
void relinkNearCallerToTrampoline(ReturnAddressPtr returnAddress, CodePtr newCalleeFunction)
{
relinkNearCallerToTrampoline(returnAddress, CodeLocationLabel(newCalleeFunction));
}
void replaceWithLoad(CodeLocationConvertibleLoad label)
{
MacroAssembler::replaceWithLoad(label);
}
void replaceWithAddressComputation(CodeLocationConvertibleLoad label)
{
MacroAssembler::replaceWithAddressComputation(label);
}
void setLoadInstructionIsActive(CodeLocationConvertibleLoad label, bool isActive)
{
if (isActive)
replaceWithLoad(label);
else
replaceWithAddressComputation(label);
}
static CodeLocationLabel startOfBranchPtrWithPatchOnRegister(CodeLocationDataLabelPtr label)
{
return MacroAssembler::startOfBranchPtrWithPatchOnRegister(label);
}
static CodeLocationLabel startOfPatchableBranchPtrWithPatchOnAddress(CodeLocationDataLabelPtr label)
{
return MacroAssembler::startOfPatchableBranchPtrWithPatchOnAddress(label);
}
void replaceWithJump(CodeLocationLabel instructionStart, CodeLocationLabel destination)
{
MacroAssembler::replaceWithJump(instructionStart, destination);
}
// This is a *bit* of a silly API, since we currently always also repatch the
// immediate after calling this. But I'm fine with that, since this just feels
// less yucky.
void revertJumpReplacementToBranchPtrWithPatch(CodeLocationLabel instructionStart, MacroAssembler::RegisterID reg, void* value)
{
MacroAssembler::revertJumpReplacementToBranchPtrWithPatch(instructionStart, reg, value);
}
void revertJumpReplacementToPatchableBranchPtrWithPatch(CodeLocationLabel instructionStart, MacroAssembler::Address address, void* value)
{
MacroAssembler::revertJumpReplacementToPatchableBranchPtrWithPatch(instructionStart, address, value);
}
private:
void* m_start;
size_t m_size;
};
} // namespace JSC
#endif // ENABLE(ASSEMBLER)
#endif // RepatchBuffer_h
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